I may never have to look at another brand again. I bought these in September and have done about 800km in them since. I should get another 200km out of them before I have to replace them which is a good return from a lightweight, fast running shoe. They are extremely comfortable with plenty of room in the toe box. If you like a really stiff racing flat they may not be for you as the ride feels cushioned but you still feel fast. I have heard some complain about getting debris in the grooves but I have never had that problem and have worn them off-road. I would where these for 5km up to a marathon. I procrastinated quite a lot before buying as they are at the top end of what I would normally pay for a running shoe, but I'm glad I finally did because I love them.